星期二, 一月 30, 2007
moodle open source course management system
Moodle is a course management system (CMS) - a free, Open Source software package designed using sound pedagogical principles , to help educators create effective online learning communities. You can download and use it on any computer you have handy (including webhosts), yet it can scale from a single-teacher site to a 50,000-student University. This site itself is created using Moodle, so check out the Moodle Demonstration Courses or read the latest Moodle Buzz.
星期一, 一月 29, 2007
How to Do Everything with PHP and MySQL
How to Do Everything with PHP and MySQL 书名：How to Do Everything with PHP and MySQL 作者：Vaswani 出版：McGraw-Hill 2005 ISBN：0072257954 格式：PDF；10MB；400页 下载链接/download link： http://rapidshare.com/files/12969753/0072257954.rar ... Source: http://www.cnshare.org/index.php/2007/01/php-mysql/
Industrial Strength C++ - Prentice Hall
Industrial Strength C++ - Prentice Hall This book greatly expands the public domain "Ellemtel" C++ coding standard. Guidelines have been carefully selected and consisely formulated to define a C++ coding standard that should be valid and usable for almost all programmers. Text and code examples explain each individual rule and recommendation. Adopting this book as the company C++ coding standard helps [...]... Source: http://www.ebooksportal.org/2007/01/industrial-strength-c-prentice-hall.ebp
History of Wireless - IEEE Press
History of Wireless - IEEE Press Important new insights into how various components and systems evolved Premised on the idea that one cannot know a science without knowing its history, History of Wireless offers a lively new treatment that introduces previously unacknowledged pioneers and developments, setting a new standard for understanding the evolution of this important technology.Starting with the background-magnetism, electricity, [...]... Source: http://www.ebooksportal.org/2007/01/history-of-wireless-ieee-press.ebp
Handbook of Applied Cryptography - CRC Press
Handbook of Applied Cryptography - CRC Press Cryptography, in particular public-key cryptography, has emerged in the last 20 years as an important discipline that is not only the subject of an enormous amount of research, but provides the foundation for information security in many applications. Standards are emerging to meet the demands for cryptographic protection in most areas of data communications. Public-key [...]... Source: http://www.ebooksportal.org/2007/01/handbook-of-applied-cryptography-crc-press.ebp
星期日, 一月 28, 2007
National Electrical Code(R) Handbook
National Electrical Code(R) Handbook The National Electrical Code® is an internationally accepted safety code for electrical and power wiring. It specifies the minimum provisions necessary for protecting people and property from hazards arising from the use of electricity and electrical equipment. Anyone involved in any phase of the electrical industry must be aware of how to use and apply [...]... Source: http://www.xpressionsz.com/archives/6200
Special Edition Using Microsoft Office Outlook 2003
Special Edition Using Microsoft Office Outlook 2003 This is the ONLY book you need to achieve maximum productivity when using this messaging and groupware application! Special Edition Using Microsoft Office Outlook 2003 is a business-focused guide to Microsoft Outlook. It focuses on maximizing user productivity with real-world techniques in real-world environments. Topics covered include using Outlook as a personal information manager; collaborating with calendars; staying organized with the Outlook Journal; using Outlook securely; working remotely with Exchange server; programming in Outlook; and using VBA in Outlook. The accompanying CD includes a FREE copy of Woody's Office Power Pack (WOPR) the #1 enhancement to Office. This software sells for $49.99 but you get it here for free with no obligations attached! About the Author Patricia Cardoza is an Exchang... Source: http://www.pdfchm.com/book/special-edition-using-microsoft-office-outlook-2003-6071/
A Short Introduction to Queueing Theory
A Short Introduction to Queueing Theory This document covers the most important queueing systems with a single service center. Only some basics are mentioned for queueing networks.... Source: http://www.freetechbooks.com/about474.html If you no longer wish to receive message like this, please contact the sender.
星期六, 一月 27, 2007
Notes on Optimization
Notes on Optimization Presents in a compact and unified manner, the main concepts and techniques of mathematical programming and optimal control to students having diverse technical backgrounds.... Source: http://www.freetechbooks.com/about483.html If you no longer wish to receive message like this, please contact the sender.
Quantitative System Performance - Computer System Analysis Using Queueing Network Models
Quantitative System Performance
Computer System Analysis Using Queueing Network Models
Edward D. Lazowska, John Zahorjan,
G. Scott Graham, Kenneth C. Sevcik
This text was published by Prentice-Hall, Inc., in 1984. It remains the definitive work on analytic modelling of computer systems. The publisher has returned the copyright to the authors, who make the material available here for viewing or downloading, in Adobe Acrobat PDF format (free Acrobat reader available here).
START HERE -- The easiest way to access the book online is through the hyperlinked Table of Contents available through this link.
Want to download the entire text to your PC? 21MB zip file may be ftp'd here.
Windows Developer Power Tools - O’Reilly
Windows Developer Power Tools - O'Reilly Software developers need to work harder and harder to bring value to their development process in order to build high quality applications and remain competitive. Developers can accomplish this by improving their productivity, quickly solving problems, and writing better code.A wealth of open source and free software tools are available for developers who want [...]... Source: http://www.ebooksportal.org/2007/01/27/windows-developer-power-tools-oreilly/ If you no longer wish to receive message like this, please contact the sender.
星期四, 一月 25, 2007
Microsoft.Press.Code.Complete.2nd.Edition.June.2004.CHM.ebook-FOS
This item was sent to you by shenjun.pku@gmail.com from Google Reader. Microsoft.Press.Code.Complete.2nd.Edition.June.2004.CHM.ebook-FOS Microsoft发布的《代码大全》第二版，CHM格式的电子书籍。 ISBN: 0-7356-1967-0 页码：960页... Source: http://0daycheck.eastgame.net/0day/archives/92531_Micr.html If you no longer wish to receive message like this, please contact the sender. Try Google Reader today: http://www.google.com/reader/
Network Coding Theory - Now Publishers
Network Coding Theory - Now Publishers
Network Coding Theory provides a tutorial on the basic of network coding theory. It presents the material in a transparent manner without unnecessarily presenting all the results in their full generality. Store-and-forward had been the predominant technique for transmitting information through a network until its optimality was refuted by network coding theory. Network [...]
Network Coding Theory provides a tutorial on the basic of network coding theory. It presents the material in a transparent manner without unnecessarily presenting all the results in their full generality. Store-and-forward had been the predominant technique for transmitting information through a network until its optimality was refuted by network coding theory. Network [...]
Operating Systems: Design and Implementation (Second Edition) - Prentice Hall
Operating Systems: Design and Implementation (Second Edition) - Prentice Hall
Most books on operating systems deal with theory while ignoring practice While the usual principles are covered in detail, the book describes a small, but real UNIX-like operating system: MINIX The book demonstrates how it works while illustrating the principles behind it Operating Systems: Design and Implementation Second Edition provides the MINIX source code The relevant selections of the MINIX code are described in detail...
Most books on operating systems deal with theory while ignoring practice While the usual principles are covered in detail, the book describes a small, but real UNIX-like operating system: MINIX The book demonstrates how it works while illustrating the principles behind it Operating Systems: Design and Implementation Second Edition provides the MINIX source code The relevant selections of the MINIX code are described in detail...
星期三, 一月 24, 2007
Content Distribution Networks: An Engineering Approach
Content Distribution Networks: An Engineering Approach
Content distribution networks (CDNs) are the most promising new techniques for coping with the huge and swiftly growing volume of Internet traffic. In essence, CDNs are groups of proxy-servers located at strategic points around the Internet and arranged so as to ensure that a download request can always be handled from the nearest server. In this, the first reference in the field, a recognized CDN pioneer describes the various technologies involved and explains how they came together to form a working system. With the help of case studies, he covers all the practical basics and provides invaluable implementation schemes.
Describes the various technologies involved and explains how they cam together to form a working system. With the help of case studies, the author covers all the practical basics and provides invaluable implementation schemes.
A thorough exploration of content distribution networks and their applications
Content distribution networks (CDNs) are the most promising new techniques for coping with the huge and swiftly growing volume of Internet traffic. In essence, CDNs are groups of proxy-servers located at strategic points around the Internet and arranged so as to ensure that a download request can always be handled from the nearest server. In this, the first reference in the field, a recognized CDN pioneer describes the various technologies involved and explains how they came together to form a working system. With the help of case studies, he covers all the practical basics and provides invaluable implementation schemes.
Describes the various technologies involved and explains how they cam together to form a working system. With the help of case studies, the author covers all the practical basics and provides invaluable implementation schemes.
A thorough exploration of content distribution networks and their applications
The exponential growth of Internet traffic has created a huge demand for techniques that improve the speed and efficiency of data delivery. One of the most important emerging approaches in this area is the use of a content distribution network (CDN), which involves employing several distributed sites to improve the scalability and responsiveness of applications. Written for network operators, ISPs, network architects, researchers, and advanced computer science students alike, here is a much-needed comprehensive overview of the fundamentals of a content distribution network. It describes the components that make up a CDN, delineates the different technologies that can be used within the network, and illustrates how several Web-based applications can be accelerated using a CDN.
The book covers such key topics as:
- Basic architecture for content distribution networks
- Applying CDNs to different business environments
- Schemes to improve the scalability of a server site
- Commonly deployed load-balancing techniques (including domain name—based techniques)
- Performance monitoring
- Managing the integrity and consistency of data
- Different interconnection arrangements within a CDN
- Managing security and trust relationships within the network
- Comparisons with application layer ad hoc content distribution networks such as Napster and Gnutella
Both an "under-the-hood" look at how CDNs work and a guide to practical applications of CDN technologies, Content Distribution Networks: An Engineering Approach is a must-have reference for anyone who operates a Web site, manages an intranet, or needs to master this rapidly emerging, powerful new technology.
About the Author
Dinesh C. Verma is Manager of the Enterprise Networking Group at the IBM T. J. Watson Research Center, Yorktown Heights, New York. He received his PhD from the University of California, Berkeley, and holds more than ten patents in the area of computer networking. A widely published expert in the field, Dr. Verma is the author of Policy-Based Networking: Architecture and Algorithms and Supporting Service Level Agreements on IP Networks. He is also an active member of the IETF and the ATM Forum.
Mobile Agents for Telecommunication Applications
Mobile Agents for Telecommunication Applications
Proceedings of the Second International Workshop, MATA, on Mobile Agents for Telecommunication Applications, held in Paris, France, September 18-20, 2000. Major paper topics included network management, Ad-hoc networks and applications, and active networks.
This publication is concerned with mobile agents for telecommunication applications. Papers have been selected from those presented during MATA'00 in Paris, the MATA reviewers having reviewed this second version of the papers presented here.
Mobile agents refer to self-contained and identifiable computer programs that can move within the network and can act on behalf of the user or another entity. Most current research work on the mobile agent paradigm has two general goals: reduction of network traffic and asynchronous interaction. These two goals stem directly from the desire to reduce information overload and to efficiently use network resources.
There are certainly many motivations for the use of a mobile agent paradigm. However, intelligent information retrieval, network and mobility management, and network services are currently the three most cited application targets for a mobile agent system.
We provide in this publication an overview of how mobile codes could be used in networking. A huge field of application is now open and a research community really exists. We have tried here to illustrate this emerging application domain of mobile agents and mobile code.
Provides an overview of how the mobile code can be used in networking with the aim of developing further intelligent information retrieval, network and mobility management, and network services.
Proceedings of the Second International Workshop, MATA, on Mobile Agents for Telecommunication Applications, held in Paris, France, September 18-20, 2000. Major paper topics included network management, Ad-hoc networks and applications, and active networks.
This publication is concerned with mobile agents for telecommunication applications. Papers have been selected from those presented during MATA'00 in Paris, the MATA reviewers having reviewed this second version of the papers presented here.
Mobile agents refer to self-contained and identifiable computer programs that can move within the network and can act on behalf of the user or another entity. Most current research work on the mobile agent paradigm has two general goals: reduction of network traffic and asynchronous interaction. These two goals stem directly from the desire to reduce information overload and to efficiently use network resources.
There are certainly many motivations for the use of a mobile agent paradigm. However, intelligent information retrieval, network and mobility management, and network services are currently the three most cited application targets for a mobile agent system.
We provide in this publication an overview of how mobile codes could be used in networking. A huge field of application is now open and a research community really exists. We have tried here to illustrate this emerging application domain of mobile agents and mobile code.
Error Correcting Coding and Security for Data Networks: Analysis of the Superchannel Concept
Error Correcting Coding and Security for Data Networks: Analysis of the Superchannel Concept
"…a comprehensive view of error coding theory and explores its use and implementation at all network layers…"
(Computing Reviews.com, February 1, 2006)
This book provides a systematic approach to the problems involved in the application of error-correcting codes in data networks.
Over the last two decades the importance of coding theory has become apparent. Thirty years ago developers of communication systems considered error-correcting coding to be somewhat exotic. It was considered as an area of interest only for mathematical engineers or mathematicians involved in the problems of engineering. Today however, theory is an important part of any textbook on communications, and the results of coding theory have become standards in data communication. The increasing demand for communications quality and the progress in information technologies has led to the implementation of error-correcting procedures in practice and an expansion in the area of error-correcting codes applications.
Error correcting coding is often analyzed in terms of its application to the separate levels within the data network in isolation from each other. In this fresh approach, the authors consider the data network as a superchannel (a multi-layered entity) which allows error correcting coding to be evaluated as it is applied to a number of network layers as a whole. By exposing the problems of applying error correcting coding in data networks, and by discussing coding theory and its applications, this original technique shows how to correct errors in the network through joint coding at different network layers.
"…a comprehensive view of error coding theory and explores its use and implementation at all network layers…"
(Computing Reviews.com, February 1, 2006)
This book provides a systematic approach to the problems involved in the application of error-correcting codes in data networks.
Over the last two decades the importance of coding theory has become apparent. Thirty years ago developers of communication systems considered error-correcting coding to be somewhat exotic. It was considered as an area of interest only for mathematical engineers or mathematicians involved in the problems of engineering. Today however, theory is an important part of any textbook on communications, and the results of coding theory have become standards in data communication. The increasing demand for communications quality and the progress in information technologies has led to the implementation of error-correcting procedures in practice and an expansion in the area of error-correcting codes applications.
Error correcting coding is often analyzed in terms of its application to the separate levels within the data network in isolation from each other. In this fresh approach, the authors consider the data network as a superchannel (a multi-layered entity) which allows error correcting coding to be evaluated as it is applied to a number of network layers as a whole. By exposing the problems of applying error correcting coding in data networks, and by discussing coding theory and its applications, this original technique shows how to correct errors in the network through joint coding at different network layers.
- Discusses the problem of reconciling coding applied to different layers using a superchannel approach
- Includes thorough coverage of all the key codes: linear block codes, Hamming, BCH and Reed-Solomon codes, LDPC codes decoding, as well as convolutional, turbo and iterative coding
- Considers new areas of application of error correcting codes such as transport coding, code-based cryptosystems and coding for image compression
- Demonstrates how to use error correcting coding to control such important data characteristics as mean message delay
- Provides theoretical explanations backed up by numerous real-world examples and practical recommendations
- Features a companion website containing additional research results including new constructions of LDPC codes, joint error-control coding and synchronization, Reed-Muller codes and their list decoding
By progressing from theory through to practical problem solving, this resource contains invaluable advice for researchers, postgraduate students, engineers and computer scientists interested in data communications and applications of coding theory.
Network Algorithmics: An Interdisciplinary Approach To Designing Fast Networked Devices - Morgan
Network Algorithmics: An Interdisciplinary Approach To Designing Fast Networked Devices - Morgan Kaufmann
In designing a network device, you make dozens of decisions that affect the speed with which it will performsometimes for better, but sometimes for worse. Network Algorithmics provides a complete, coherent methodology for maximizing speed while meeting your other design goals.Author George Varghese begins by laying out the implementation bottlenecks that are most often encountered [...]
In designing a network device, you make dozens of decisions that affect the speed with which it will performsometimes for better, but sometimes for worse. Network Algorithmics provides a complete, coherent methodology for maximizing speed while meeting your other design goals.Author George Varghese begins by laying out the implementation bottlenecks that are most often encountered [...]
Operating Systems: Design and Implementation (Second Edition) - Prentice Hall
Operating Systems: Design and Implementation (Second Edition) - Prentice Hall
Most books on operating systems deal with theory while ignoring practice. While the usual principles are covered in detail, the book describes a small, but real UNIX-like operating system: MINIX. The book demonstrates how it works while illustrating the principles behind it. Operating Systems: Design and Implementation Second Edition provides the MINIX source code. The [...]
Most books on operating systems deal with theory while ignoring practice. While the usual principles are covered in detail, the book describes a small, but real UNIX-like operating system: MINIX. The book demonstrates how it works while illustrating the principles behind it. Operating Systems: Design and Implementation Second Edition provides the MINIX source code. The [...]
Operating Systems Concepts - John Wiley & Sons
Operating Systems Concepts - John Wiley & Sons
Celebrating its 20th anniversary, Silberschatz: Operating Systems Concepts, Sixth Edition, continues to provide a solid theoretical foundation for understanding operating systems. The Sixth Edition offers improved conceptual coverage and added content to bridge the gap between concepts and actual implementations. Threads has been added to this latest edition and includes coverage of Pthreads and Java [...]
Celebrating its 20th anniversary, Silberschatz: Operating Systems Concepts, Sixth Edition, continues to provide a solid theoretical foundation for understanding operating systems. The Sixth Edition offers improved conceptual coverage and added content to bridge the gap between concepts and actual implementations. Threads has been added to this latest edition and includes coverage of Pthreads and Java [...]
星期二, 一月 23, 2007
Fundamentals of Project Management
Fundamentals of Project Management
Quality Progress "It contains alot of wisdom at a small cost." --This text refers to the Paperback edition. Book Description In today's time-based and cost-conscious global business environment,...
This is a summary of this blog, more you can find in the blog !
Economists’ Mathematical Manual, 4th Edition
Economists' Mathematical Manual, 4th Edition
书名：Economists' Mathematical Manual, 4th Edition 经济学家数学手册
作者：Knut Syds
星期一, 一月 22, 2007
Brain Storm: Tap into Your Creativity to Generate Awesome Ideas and Remarkable Results
Brain Storm: Tap into Your Creativity to Generate Awesome Ideas and Remarkable Results
书名：Brain Storm: Tap into Your Creativity to Generate Awesome Ideas and Remarkable Results
作者：Jason Rich
出版：Career Press 2003
ISBN：1564146685
格式：CHM；5.6MB;187页
下载链接/download url：
http://rapidshare.com/files/12424718/1564146685.rar
Communications Systems
Communications Systems
A new edition that takes students to the cutting edge and back!
Extensively revised and updated, this new fourth edition of COMMUNICATION SYSTEMS is the most complete undergraduate textbook on the theories and principles behind today's most advanced communications systems.
New features include:
- MATLAB computer experiments that demonstrate important aspects of communication theory
- Expanded coverage of emerging digital technologies, such as digital subscriber line (DSL), carrierless amplitude modulation/phase modulation (CAP), and discrete multi-tone (DMT)
- Dozens of examples that relate theory to real-world communication systems
Superbly organized, the text skillfully guides students through topics ranging from pulse modulation to passband digital transmission, and from random processes to error-control coding. Throughout, Haykin presents difficult concepts in language that students can easily understand.
星期日, 一月 21, 2007
让你真正了解世界的十本书
让你真正了解世界的十本书
我们生活在这个纷繁的世界，面对变幻莫测的大自然和熙熙攘攘的人类，岂止有十万个为什么要问？因此，下面这十本书或许能帮助我们真正理解所身处的这个世界。
我们生活在这个纷繁的世界，面对变幻莫测的大自然和熙熙攘攘的人类，岂止有十万个为什么要问？因此，下面这十本书或许能帮助我们真正理解所身处的这个世界。
一、闯入神秘的世界 ——《梦的解析》(作者:弗洛伊德)
这本书原本计划于1899年出版，但是，一位颇富眼光的出版商看出了此书的价值，将它的出版定在具有纪念意义的1900年。
《梦的解析》作为一本具有划时代意义之作，其伟大之处并不在于对"性"的惊世骇俗的探讨，而恰恰是那些关于梦的独特、新颖的见解，引导人们推开"梦"这扇大门，第一次真正走进人类深藏的内心世界，发现无法被意识所控制的潜意识，竟然蕴含了如此丰富的心理内容和巨大的创造力。弗洛伊德用一种最理性的声音诉说了人类的无理性，从更深的层次上阐述了人类的生存状况。
有人评价说，尽管在弗洛伊德之前，潜意识问题就已若隐若现地在一些作品中流露，但就像利夫和布伦丹曾触及到美洲海岸一样，只有弗洛伊德证明了潜意识确实存在，并对其丰富多彩和惊恐可怖加以揭示，是这个领域的哥伦布。
弗洛伊德对20世纪人类的焦虑和梦魇从人性上进行了探讨，他所创立的精神分析学派成为20世纪最流行的人本主义心理学派，是哲学上法兰克福学派"批评理论"的重要渊源，今天，在超现实主义、自然主义、抽象主义的文学艺术作品中，我们都可以感受到它的巨大影响。
二、靠推论创造奇迹——《论运动物体的电动力学》(作者:爱因斯坦)
1905年，一位供职于瑞士国家专利局、名叫爱因斯坦的26岁德国人，在德国科学杂志《物理年报》上连续发表了三篇论文。其中《论运动物体的电动力学》，提出了根本有别于传统观念的空间、时间理论。
在《论运动物体的电动力学》中，爱因斯坦一改以往人们头脑中的观念，论证了时间和空间是相对的，只有独立于观察者之外的光速是个常数。爱因斯坦证明，当物体的速度接近光速时，其长度就会减小，质量就会增加，时间就会放慢。由此推论，假如物体的速度与光的速度相同时，其长度为0，质量不会再增加，而且时间也就停止了。
爱因斯坦根据这种不可能性得出了一个结论：任何物体都不会以光速和超过光速运动。这项被称为"相对论"的理论弥补了牛顿物理学长达两个世纪的不足，爱因斯坦将时间与空间相结合，创立了新的四维宇宙空间的学说。
1916年，阿尔贝特&S226;爱因斯坦发表了《广义相对论的基础》，完成了他对牛顿物理学的修正。这一次，爱因斯坦把"物质"的概念引入了他的相对论中，他认为，物质也是空间的一种属性，同样与时间密不可分。
相对论彻底改变了人们对时空观的认知，带来了整个物理学的革命。值得一提的是，尽管对于绝大多数人而言，相对论显然是一个艰深的理论，但爱因斯坦却一直没有放弃将它介绍给普通大众的努力。
相对论被认为是"人类思想史中最伟大的成就之一"，其中人们最熟悉的著名公式，E＝mc2，为人类掌握核技术打下了理论基础。在爱因斯坦的一生中，他一直被公认为本世纪最伟大的思想家。
三、因思考而更迷惘 ——《太阳照样升起》 (作者:海明威)
"一个人并不是生来要给打败的，你尽可以把他消灭掉，可就是打不败他。"——欧内斯特&S226;海明威
1926年，欧内斯特·海明威的小说《太阳照样升起》出版后，"迷惘的一代"这一称呼迅速被人们接受，这部小说被奉为当时青年人的《圣经》。使用海明威式的简短而厌世的语言成了人们交谈的时尚，而那种粗犷而敏感的叙事风格，同样为人们所喜爱。
《太阳照样升起》是作者最敏锐地捕捉到社会脉搏的作品。作为一位自传性很强的作家，海明威本身就是那些在战争严重摧残的道德环境中成长起来的青年中的一员。他参加过那场令人刻骨铭心的战争，他目睹了军功章在战后市场上被廉价出售，他身边的年轻人整日寻欢作乐，醉生梦死。这使海明威更加迷惘痛心。
《太阳照样升起》的原型是作者所处的包括作家、艺术家和需求刺激的社会名流的圈子。但它却写出了普通大众的真实的生存状态。
他笔下的人物，无法投身于任何伟大的事业，而只能在英勇的、壮美的、有时甚至是残酷的场景中寻求生存的意义。
"迷惘的一代"并非浑沌的一代，正因为思考，才会迷惘。纵观海明威一生作品中创造的主人公，也经历了一个由迷惘空虚到勇敢抗争的过程。事实上，"迷惘的一代"中的绝大多数人在十几年后，又投身到了为正义和生存而战的反法西斯斗争中。《太阳照样升起》敏锐而准确地捕捉到了时代精神，其意义已经远远超出了文学的范畴。
时至今日，读者仍然会被其中蕴含的苍凉所打动。
四、挣脱漩涡的方舟 ——《就业、利息和货币通论》(作者：凯恩斯)
"有一个基本心理法则，我们可以确信不疑。一般而论，当所得增加时，人们将增加其消费，但消费的增加，没有其所得增加得那么多。" ——J．M．凯恩斯
1929年，一场空前的经济危机席卷西方，使资本主义世界陷入了严重的萧条和失业的漩涡之中，股市的崩溃，使人们终生的积蓄在顷刻间化为乌有。但是，经济学家们仍然认为，资本主义制度是一个自我调节的系统，任何干预都是有害的。因此，在最初的几年，西方各国政府都采取了一种袖手旁观的态度，甚至坚信"繁荣近在咫尺"。
危机一发而不可收，1933年，西方国家的失业人口已达3千万，是1929年的5倍多。对于普通人而言，30年代初，找到一份工作，是最为迫切的一件事。人们在问：这场大萧条何时能够终结，怎样才能制止经济衰退？
在苦苦的期待之中，1936年，英国经济学家J．M．凯恩斯在其《就业、利息和货币通论》中，终于为挽救资本主义经济开出了"药方"。在书中，凯恩斯对各国政府自由放任的经济政策进行了猛烈的攻击。凯恩斯断言，市场不是万能的。在对大萧条进行了细致的研究后，凯恩斯提出了一国总产量和就业量取决于"有效需求"的理论。
他认为，增加资本的关键是增加需求，而这需要依靠大量、稳定的就业。失业的直接原因是社会对企业生产产品的需求不断减少，导致资本家不再增加投资，而引发就业减少，造成工人失业。消除失业的办法，在于实行国家干预。当货币政策刺激投资增长的力度不足以完全实现市场调节时，国家必须使用财政政策，把资金直接投资于"公共工程"，以便扩大内需。
《就业、利息和货币通论》是西方经济学一部里程碑式的著作，在西方国家引起了巨大的轰动，迅速被各国广泛采纳。凯恩斯甚至被誉为"经济学领域的哥白尼"。有人说："如果不读凯恩斯的著作，就没有资格谈论经济学。"事实证明，凯恩斯的经济学观点不但避免了大萧条中的资本主义经济所遭受灭顶之灾，而且在高经济增长、低失业率的五六十年代，凯恩斯主义及其衍生的宏观经济理论，被惊人地证明富有成效。
作为现代最有影响的经济学家，凯恩斯的《通论》在西方同《物种起源》和《资本论》相提并论，直至今天，它仍在为西方经济学提供着学术源泉。
五、存在着并自由着 ——《存在与虚无》（作者：保罗·萨特)
"我的位置将不是一个聚焦点，而是一个出发点。" ——让－保罗·萨特
1943年，法国思想家让－保罗&S226;萨特的《存在与虚无》一书，树立起存在主义的大旗，号召人们在危机中寻求自由和光明。从30年代起，萨特就被认为是一个社会的反抗者，一个"不断地以个人的名义和人们自由的名义向现代世界提出抗议，想恢复人的价值"的哲学家。
萨特的思想一生都在变化，但"人"和"自由"一直是他理论的出发点。在萨特看来，人之所以比物高贵，就是因为人可以自由决定自己的存在，自由地选择自己的本质。萨特说出了那个时代许多人的心理感受：世界令人失望，人生充满荒谬。但萨特并不因此绝望。他告诉人们，人类的希望在于，用自己的行动反抗荒诞的世界。因为人是自由的，人是一切价值的创造者，没有上帝，没有任何超人的力量，更没有任何他人能改变你的命运。人是成为英雄还是成为懦夫，全靠你自己去选择。每个人都应该自由地选择自己的道路，为自己的生活创造独特的价值。
在《存在与虚无》中，萨特以人为中心，号召人们在无法改变的情境下，通过自由选择不断创造自己的存在，承担自由的重负，对自己、对整个世界承担责任。这种哲学引起了饱受战争创伤、目睹人性惨遭践踏的迷惘的一代的强烈共鸣。成千上万的青年人自封为"存在主义者"，身穿"存在主义服装"，过"存在主义人生"。人们在咖啡馆里谈论存在主义、在剧院里观看存在主义。此前，还没有一种哲学思潮能够如此深入人心，存在主义运动从哲学和文学运动，扩展成了一场群众运动。
七、指出社会发展方向————《资本论》（ 作者：卡尔·马克思）
《资本论》的出版时间是1867-1894年。
马克思生前只看到"资本论"这一大部头著作的第一卷得以出版，他的赞助人恩格斯编辑出版了马克思起草的另外两卷。《资本论》揭示了资本主义是人类社会发展的一个丑陋阶段，资本家不可避免而且毫无道德的通过工资剥削压榨工人，来获取最大利润。马克思在这里深入地分析了商品,揭示了价值规律。
虽然马克思没能具体预知21世纪的资本主义和现代议会制政府基础上的自由富裕的社会，他没想到资产阶级也在学习<资本论>并正在克服自身危机和矛盾。但他通过分析商品社会后指出资本主义必然消亡等观点是多么有先见之明！
八、揭示危机的本源 ——《全球通史》（作者：斯塔夫里阿诺斯 ）
"人们十分自然地欢迎和采纳那些能提高生产率和生活水平的新技术，但是，人们却拒绝接受新技术所必需的社会变化。" ——斯塔夫里阿诺斯
世界文明是全人类的共有财富，然而，世界史研究，作为一门独立的学科，却始终没有摆脱以西方为中心的研究角度。因此，1970年，当斯塔夫里阿诺斯的《全球通史》出版时，格外引人注目。这部通史被认为是第一部由历史学家运用全球观点，囊括全球文明而编写的世界历史。
《全球通史》分为《1500年前的世界》和《1500年后的世界》两部分。作者认为，整个世界是一个不可分割的整体，因此，他将目光投向了那些对人类历史进程产生了巨大影响的历史事件，着重分析了各种历史事件之间的有机联系和相互作用。作者在记录西方文明发展的同时，同样对在儒家文化、阿拉伯文明等影响下的各国政治、经济、文化作了全面的分析，充分肯定了各民族对世界文明进程所作出的贡献。作者认为，1500年以前，各种文明是相对平行发展的，而在这之后，随着"发现新大陆"，各地区文明才真正走上了相互交流之路。
《全球通史》并不是简单地对人类文明的进程加以总结，它的精华在于，通过对历史现象的分析，对历史的发展提出了自己创造性的见解。作者对20世纪，尤其是第二次世界大战以来至70年代的这段历史给予了格外的关注。对于人类所面临的越来越多的社会问题，作者认为，其根源在于技术革命在全球范围内突飞猛进地发展，而社会革命却相对沉寂。正是这两种革命之间的时间滞差，使整个世界陷入了空前的危机。由于具有深刻的思想性和深厚的社会责任感，《全球通史》获得了极高的评价，被誉为当今社会的"救世箴言"。
九、破解时间的咒语 ——《时间简史》(斯蒂芬·霍金 )
"时间－空间在大爆炸奇点处开始，并会在大挤压奇点处或黑洞的一个奇点处结束。任何抛进黑洞的东西都会在奇点处被毁灭。" ——斯蒂芬·霍金
对于大多数人来说，1988年出版的一本科普读物《时间简史》，使他们开始知道斯蒂芬&S226;霍金，这位英国物理学家和宇宙论学者的名字。其实，早在1974年，霍金就曾使人为之侧目。当时他提出了一个令所有人震惊的结论。他断言，黑洞能够释放放射线。而根据科学界的"常识"，黑洞是一种假设的衰弱星体，其吸引力极强，甚至连光都无法摆脱其作用，怎么可能释放放射线呢？据说，霍金在牛津大学附近举行的一次天文学会议上所做的这番讲话曾把他的一位同行气得暴跳如雷。
事实上，霍金一直试图将爱因斯坦的相对论同量子理论综合起来，这也是爱因斯坦和其他科学家一直未能获得成功的领域。霍金提出的方程式有助于揭示，为什么宇宙在150亿年的时间里由一点扩展成无限，以及为什么它又以一种被称为"宇宙险境"的方式对其本身进行收缩。
因为他的研究，霍金被誉为本世纪继爱因斯坦后最重要的广义相对论学者和宇宙哲学家。
《时间简史》是一部讲述宇宙奥秘的科普读物，试图解答人类最古老的命题：时间是有始有终的吗？宇宙是无限的吗？在霍金展示给人们的新的宇宙图景中，他在经典物理学的框架内，证明了黑洞和大爆炸奇点的不可避免性；而在量子物理学的框架内，他研究的黑洞辐射理论证明，大爆炸的奇点不但被量子效应所抹平，而且宇宙正是起始于此。
十、聆听未来的召唤 ——《未来之路》(比尔·盖茨 )
"这是一个绝妙的生存时代，从来也没有过这么多的机会，让人
去完成从前根本无法做到的事情。"——比尔·盖茨
20世纪90年代，对于今天的我们来说，实在是太近了，近到来不及仔细地回味，近到看不清我们昨天所亲历的一切，会对未来产生怎样的影响。因此，选择比尔&S226;盖茨的《未来之路》，更主要的原因不是因为其非同凡响，而是它代表了对人类必将跨入信息时代的信念和对未来的憧憬。
提起盖茨，有人会带着复杂的表情说："哦，那个没有读完大学的家伙。"但是没有人会否认，这是一个富有传奇色彩的名字。45岁的盖茨已经在世界首富的宝座上坐了很长的时间。在短短20年内，从白手起家到拥有150亿美元的个人财产，与其说这是盖茨创造的奇迹，不如说是信息技术创造的奇迹。
简单的生产工具的运用，使人的手足得以延长；蒸汽、电力的使用，增强了人的体力；而信息技术的革命，拓展了人的视野，使个人的智力得以延伸。与工业时代相比，在信息时代，社会的生产和财富的积累方式都将发生翻天覆地的变化。而在世纪之交，人类也正在完成这两个时代的跨越。
在《未来之路》中，这位微软公司的总裁希望把他"对技术前景的展望，以及时不时冒出来的想法与这个时代共享"。盖茨详尽的阐述了"信息高速公路"对人类未来生活的影响。"更重要的是，我们可以对技术进步的优缺点都加以广泛的探讨，以便让社会成为一个整体……"。
来源：世界经理人文摘
星期六, 一月 20, 2007
Mathematics for Electrical Engineering and Computing
Mathematics for Electrical Engineering and Computing
书名：Mathematics for Electrical Engineering and Computing
作者：Mary Attenborough
出版：Newnes 2003
ISBN：075065855X
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How to Study, 2nd Edition
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书名：How to Study, 2nd Edition (How to Study: Use Your Personal Learning Style to Help You Succeed When It Counts)
作者：Gail Wood
出版：Learning Express 2nd，2000
ISBN：157685308X
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MatLab Programming
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The Art of Software Architecture: Design Methods and Techniques - Wiley
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* With the help of numerous examples, Albin clearly shows how to incorporate Java, XML, SOAP, ebXML, and BizTalk when designing true distributed business systems
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朱威廉:我为什么不愿当Google中国总裁
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星期五, 一月 19, 2007
zz Wikipedia: OSI model
Wikipedia: OSI model - Wikipedia, the free encyclopedia
It has been suggested that this article or section be merged with Open Systems Interconnection. ( Discuss) 
OSI ModelThe OSI model divides the functions of a protocol into a series of layers. Each layer has the property that it only uses the functions of the layer below, and only exports functionality to the layer above. A system that implements protocol behaviour consisting of a series of these layers is known as a ' protocol stack' or 'stack'. Protocol stacks can be implemented either in hardware or software, or a mixture of both. Typically, only the lower layers are implemented in hardware, with the higher layers being implemented in software. 
The OSI reference modelThis OSI model is roughly adhered to in the computing and networking industry. Its main feature is in the interface between layers which dictates the specifications on how one layer interacts with another. This means that a layer written by one manufacturer can operate with a layer from another (assuming that the specification is interpreted correctly). These specifications are typically known as Requests for Comments or "RFC"s in the TCP/IP community. They are ISO standards in the OSI community.
OSI model
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| OSI Model | |
|---|---|
| 7 | Application layer |
| 6 | Presentation layer |
| 5 | Session layer |
| 4 | Transport layer |
| 3 | Network layer |
| 2 | Data link layer |
| 1 | Physical layer |
The Open Systems Interconnection Reference Model ( OSI Reference Model or OSI Model for short) is a layered, abstract description for communications and computer network protocol design, developed as part of the Open Systems Interconnection initiative. It is also called the OSI seven layer model.
[ edit] Purpose
Usually, the implementation of a protocol is layered in a similar way to the protocol design, with the possible exception of a 'fast path' where the most common transaction allowed by the system may be implemented as a single component encompassing aspects of several layers.
This logical separation of layers makes reasoning about the behavior of protocol stacks much easier, allowing the design of elaborate but highly reliable protocol stacks. Each layer performs services for the next higher layer and makes requests of the next lower layer. As previously stated, an implementation of several OSI layers is often referred to as a stack (as in TCP/IP stack).
The OSI reference model is a hierarchical structure of seven layers that defines the requirements for communications between two computers. The model was defined by the International Organization for Standardization in the ISO standard 7498-1. It was conceived to allow interoperability across the various platforms offered by vendors. The model allows all network elements to operate together, regardless of who built them. By the late 1980's, ISO was recommending the implementation of the OSI model as a networking standard.
Of course, by that time, TCP/IP had been in use for years. TCP/IP was fundamental to ARPANET and the other networks that evolved into the Internet. (For significant differences between TCP/IP and ARPANET, see RFC 871.)
Only a subset of the whole OSI model is used today. It is widely believed that much of the specification is too complicated and that its full functionality has taken too long to implement, although there are many people who strongly support the OSI model. [1]
[ edit] Description of OSI layers
| OSI Model | |||
|---|---|---|---|
| | Data unit | Layer | Function |
| Host layers | Data | Application | Network process to application |
| Presentation | Data representation and encryption | ||
| Session | Interhost communication | ||
| Segments | Transport | End-to-end connections and reliability | |
| Media layers | Packets | Network | Path determination and logical addressing (IP) |
| Frames | Data link | Physical addressing (MAC & LLC) | |
| Bits | Physical | Media, signal and binary transmission | |
[ edit] Layer 7: Application Layer
The Application layer provides a means for the user to access information on the network through an application. This layer is the main interface for the user(s) to interact with the application and therefore the network. Some examples of application layer protocols include Telnet, applications which use File Transfer Protocol (FTP), applications which use Simple Mail Transfer Protocol (SMTP) and applications which use Hypertext Transfer Protocol (HTTP). Applications built to utilize a protocol, such as FTP, should not be confused with the protocols themselves, which often reside at the session layer.
[ edit] Layer 6: Presentation Layer
The Presentation layer transforms data to provide a standard interface for the Application layer. MIME encoding, data compression , data encryption and similar manipulation of the presentation is done at this layer to present the data as a service or protocol developer sees fit. Examples: converting an EBCDIC-coded text file to an ASCII-coded file, or serializing objects and other data structures into and out of, e.g., XML.
[ edit ] Layer 5: Session Layer
The Session layer controls the dialogues (sessions) between computers. It establishes, manages and terminates the connections between the local and remote application. It provides for either duplex or half-duplex operation and establishes checkpointing, adjournment, termination, and restart procedures. The OSI model made this layer responsible for "graceful close" of sessions, which is a property of TCP, and also for session checkpointing and recovery, which is not usually used in the Internet protocols suite.
[ edit ] Layer 4: Transport Layer
The Transport layer provides transparent transfer of data between end users, thus relieving the upper layers from any concern while providing reliable data transfer. The transport layer controls the reliability of a given link through flow control, segmentation/desegmentation, and error control. Some protocols are state and connection oriented. This means that the transport layer can keep track of the packets and retransmit those that fail. The best known example of a layer 4 protocol is the Transmission Control Protocol (TCP). The transport layer is the layer that converts messages into TCP segments or User Datagram Protocol (UDP), Stream Control Transmission Protocol (SCTP), etc. packets.
[ edit ] Layer 3: Network Layer
The Network layer provides the functional and procedural means of transferring variable length data sequences from a source to a destination via one or more networks while maintaining the quality of service requested by the Transport layer. The Network layer performs network routing functions, and might also perform segmentation/desegmentation, and report delivery errors. Routers operate at this layer―sending data throughout the extended network and making the Internet possible (also existing at layer 3 (or IP) are switches). This is a logical addressing scheme �C values are chosen by the network engineer. The addressing scheme is hierarchical. The best known example of a layer 3 protocol is the Internet Protocol (IP).
[ edit ] Layer 2: Data Link Layer
The Data Link layer provides the functional and procedural means to transfer data between network entities and to detect and possibly correct errors that may occur in the Physical layer. The best known example of this is Ethernet. Other examples of data link protocols are HDLC and ADCCP for point-to-point or packet-switched networks and Aloha for local area networks. On IEEE 802 local area networks, and some non-IEEE 802 networks such as FDDI, this layer may be split into a Media Access Control (MAC) layer and the IEEE 802.2 Logical Link Control (LLC) layer. It arranges bits from physical layer into logical chunks of data, known as frames.
This is the layer at which the bridges and switches operate. Connectivity is provided only among locally attached network nodes forming layer 2 domains for unicast or broadcast forwarding. Other protocols may be imposed on the data frames to create tunnels and logically separated layer 2 forwarding domains.
[ edit ] Layer 1: Physical Layer
The Physical layer defines all the electrical and physical specifications for devices. This includes the layout of pins, voltages, and cable specifications. Hubs, repeaters, network adapters and Host Bus Adapters (HBAs used in Storage Area Networks) are physical-layer devices. The major functions and services performed by the physical layer are:
- Establishment and termination of a connection to a communications medium.
- Participation in the process whereby the communication resources are effectively shared among multiple users. For example, contention resolution and flow control .
- Modulation, or conversion between the representation of digital data in user equipment and the corresponding signals transmitted over a communications channel. These are signals operating over the physical cabling (such as copper and fiber optic) or over a radio link.
Parallel SCSI buses operate in this layer. Various physical-layer Ethernet standards are also in this layer; Ethernet incorporates both this layer and the data-link layer. The same applies to other local-area networks, such as Token ring, FDDI, and IEEE 802.11, as well as personal area networks such as Bluetooth and IEEE 802.15.4.
[ edit] Interfaces
In addition to standards for individual protocols in transmission, there are also interface standards for different layers to talk to the ones above or below (usually operating-system�Cspecific). For example, Microsoft Windows' Winsock, and Unix's Berkeley sockets and System V Transport Layer Interface, are interfaces between applications (layers 5 and above) and the transport (layer 4). NDIS and ODI are interfaces between the media (layer 2) and the network protocol (layer 3).
[ edit] Examples
[ edit] Humor
- The 7 layer model is sometimes humorously extended to refer to non-technical issues or problems. A common joke is the 10 layer model, with layers 8, 9, and 10 being the "user", "financial", and "political" layers, or the "money", "politics", and "religion" layers. Similarly, network technicians will sometimes refer to "layer-eight problems", meaning problems with an end user and not with the network.
- The OSI model has also been jokingly called the " Taco Bell model", since the restaurant chain has been known for their 7 layer burrito.
- Dick Lewis uses an analogy of James Bond delivering classified messages to illustrate the seven-layer model.
[ edit] See also
[ edit] External links
- ISO standard 7498-1:1994 ( ZIP format)
- Cybertelecom ― Layered Model of Regulation
- OSI Model Tutorial
- OSI Model Tutorial in Flash
- Computer Networks and Protocol ― The OSI Reference Model
- OSI Reference Model ― The ISO Model of Architecture for Open Systems Interconnection PDF, Hubert Zimmermann, IEEE Transactions on Communications, vol. 28, no. 4, April 1980, pp. 425 - 432.
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